From the Guidelines
Breast-fed babies' bilirubin levels should be less than 12 mg/dL at 20 days of age, considering the normal physiological phenomenon of breast milk jaundice. Breast-fed babies often have slightly higher bilirubin levels than formula-fed infants due to breast milk jaundice, which typically peaks around 10-14 days of life and gradually decreases thereafter 1. This occurs because certain components in breast milk may inhibit the liver's ability to process bilirubin efficiently. Key factors influencing bilirubin levels in breast-fed babies include:
- Feeding frequency: 8-12 times per day to promote bowel movements that help eliminate bilirubin
- Adequate weight gain and no signs of lethargy or other concerning symptoms
- Monitoring bilirubin levels, with no intervention typically needed for breast milk jaundice as long as the baby is feeding well. If bilirubin levels exceed 15 mg/dL at this age or the baby shows signs of dehydration or poor feeding, medical evaluation is warranted 1.
From the Research
Normal Bilirubin Levels in Breast-Fed Babies
- The normal bilirubin level for a breast-fed baby is not explicitly stated for day 20 in the provided studies.
- However, a study from 1986 2 found that the 95th percentile for breast-fed infants is a serum bilirubin level of 14.5 mg/dL, and the 97th percentiles are 14.8 mg/dL.
- It is also mentioned in the same study that investigations for the cause of hyperbilirubinemia in healthy breast-fed infants may not be indicated unless the serum bilirubin level exceeds approximately 15 mg/dL.
Factors Affecting Bilirubin Levels
- Breast-feeding is significantly associated with hyperbilirubinemia, even in the first three days of life 2.
- Beta-glucuronidase enzyme in breast milk may contribute to neonatal hyperbilirubinemia in breast-fed babies by facilitating intestinal reabsorption of bilirubin 3.
- Hematocrit levels can also affect bilirubin photoalteration, with higher hematocrit levels reducing the efficacy of phototherapy 4.
Phototherapy and Bilirubin Levels
- Phototherapy is a common treatment for neonatal hyperbilirubinemia, and its efficacy can be affected by hematocrit levels 4.
- A study from 2015 5 found that combining phenobarbital with phototherapy can enhance the decline of total serum bilirubin and may decrease the need for blood exchange transfusion in newborns with isoimmune hemolytic disease.